<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>输入框图标</title>
<style>
input[type=text] {
    width: 100%;
    box-sizing: border-box;
    border: 2px solid #ccc;
    border-radius: 4px;
    font-size: 16px;
    background-color: white;
    background-image: url('https://static.runoob.com/images/mix/searchicon.png');
    background-position: 10px 10px;
    background-repeat: no-repeat;
    padding: 12px 20px 12px 40px;
}
</style>
</head>
<body>
    <p>输入框按钮：</p>
    <form>
        <input type="text" name="search" placeholder="搜索...">
        </form>
        </body>
</html>